Java tutorial
//package com.java2s; //License from project: Apache License import java.util.Iterator; import java.util.Map; import java.util.concurrent.ExecutionException; import java.util.concurrent.Future; public class Main { public static void checkFutures(Map<? extends Object, Future<Void>> futures, int maxSize) throws InterruptedException, ExecutionException { while (futures.size() > maxSize) { for (Iterator<? extends Object> i = futures.keySet().iterator(); i.hasNext();) { Object key = i.next(); futures.get(key).get(); i.remove(); } } } }